Democratic hopeful for the US Senate Mass. US Reps. Stephen Lynch, left, and Edward Markey, center, prepare for a televised debate as moderator R.D. Sahl, right, looks on at the WCVB-TV studios in Needham, Mass., Wednesday, March 27, 2013.

In their first televised debate before a special US Senate election, Rep. Stephen Lynch sought to make up some ground against front-runner Rep. Ed Markey, framing the race as a debate over which of them really stands up for ordinary citizens.

The two Democrats, in their bids for the seat recently vacated by John Kerry (D), sparred over issues ranging from health care and abortion to the economic plight of Bay State fishermen.

Representative Lynch challenged his rival to explain a vote to bail out the banking industry in 2008, and his ties to big telecommunications firms.

“There seems to be a pattern,” Lynch said in the Wednesday match-up. “You’re siding with the big guys against the little guys…. What’s up with that?”

Representative Markey, the longest-serving member of the state’s congressional delegation, parried the attacks by saying he has used his career in the House to break up telecom monopolies, and that the banking bailout was needed to rescue the whole economy from the risk of a severe depression.

“We could not allow the banking system to collapse onto the hopes and dreams of every family in America,” Markey said.

Lynch is pitching himself as the centrist in the race, at a time when Congress needs to break a pattern of partisan gridlock. Contrasting himself with both the “hard left” and “hard right,” he said “I don't work for Nancy Pelosi,” and that if elected to the Senate he won’t work for majority leader Harry Reid.

In a state with a strongly Democratic electorate, Markey’s stronger liberal credentials may be one reason he’s been polling ahead of Lynch. He said the vote for Obamacare, the Affordable Care Act, was the “the proudest vote of my career,” and that he’s supported abortion rights for three decades.

Lynch identifies himself as pro-life, while also saying he’s against overturning the Supreme Court’s Roe vs. Wade decision. He praised the group Planned Parenthood (which has endorsed Markey) because reducing unwanted pregnancies is “the real goal” in the quest to bring down abortion rates.

Lynch was one of the rare House Democrats who voted against the Affordable Care Act. He explained his vote by saying the measure raised taxes for businesses and lacked a “public option” health plan to spur competition in the insurance industry.

On the Republican side, a handful of less-known Massachusetts politicians are competing for the nomination: former US attorney Michael Sullivan, state Rep. Daniel Winslow, and Gabriel Gomez, a private equity investor and former Navy SEAL.